Fundus cameras are well known in the ophthalmology instrumentation art for use in photographing the optic nerve and other internal features of the eye. A typical fundus camera system, as shown in FIG. 1, includes a fundus camera for making still photographs, a video camera for aligning the fundus camera, a computer system for storing and manipulating video data, and a monitor for displaying the video data transmitted from the video camera.
Interfacing the video system to the fundus camera is traditionally implemented in one of two ways. In the first method, conventional microscope optics are incorporated into the fundus camera and an optical splitter or reflex mirror directs the image between a video camera and the recording film mounted in the fundus camera back. In the second method, a video interface is mounted into the fundus camera back. Both methods have met with less than optimal results. The microscope splitting technique requires the use of relatively expensive optical equipment. The camera back replacement method yields large, relatively unwieldy systems. Both interface techniques tend to disturb the natural balance of the fundus camera and make the system more susceptible to incidental room vibrations. Attempts to stabilize the architectures have resulted in increased cost and weight.